logoFarmingTechnologies
...Follow the track to the future.....by Sanguin.
Vehicle testing                                                                                                                                             language
                                Vehicle Data Logging: why log data
Blue leader
Traction and Slip figure 
Power to the ground

The measure of the vehicle performance  is the first step  for the vehicle devepment.
The measure of all energy parameters  like power, torque, vehicle speed, traction, fuel consumption, spec f.c.,... performed when the vehicle is running and all parameters change quickly, in one word the Dynamic Measure, provides results and values slightly (and in some case noticeably) different from
the Stationary test (nothing changes, or changes are very slow, d/dt=0).
The excellent knowledge of the instrumentation chain is the key point to ensure reliable data logging and analysis, that, in addition to most accurate recording in the  real operative conditions,
ensures the best support for any vehicle development.


                     Comparative Vehicle Testing
Logging Chain

Few data to understand the analysis

The reliable test procedure, combined with the best expertise about both data logging and Tractor technical background, are the basis to achieve  the excellence in terms  Comparison between Competitors: the test objective is to provide an energy balance in Field, precisely calculating the power flows through each vehicle group/part of the vehicle for each main operation (ploughing, power harrowing, haulage,..)


                    Vehicle architecture
Front Visibility
Control Ergonomy

More and more:
We can calculate the view from the operator station that is the vehicle shadow to the ground, we can support the control ergonomy suggesting the best position, we can even study Noise and vibrations probelems by spectral analysis.



                    Pto Test
               
PTO Test

We can test Power and Torque, up to 450 hp, by a powerful and precise dynamometer to Pto shaft and even to the engine flywheel.
We can perform:


                 Tractor performance while field working
     
 
Performance Panel 

When i started this job , about 15 years ago, the main challenge was succeeding to measure and calculate two key points while field operating:
The Second step was to compare different Competitors operating in the same way, then the Third step was achieving Data and Calculation Real Time and send them to RF.... Even if some more work is required, now everything has been done.
Currently, even if analog signals (from load cells, frequency, potentiometers, radars,...) are sampled at 2 kHz or higher scan rate (depending on circumstances), the results of calculations are supplied 20 times per second and realigned in the time scale with those of analog data that do not require any calculation (just averaged), CAN bus data, GPS data... in other words the final results traces are refreshed at 20 Hz.
 


Traction Slip Characteristic

This figure is frequently required to evaluate the traction capability of both tractor and tyres. Fixing a certain ground, for tractors the traction/slip figure depends on the general setting and design: total weight, weight distribution on the axles, wheelbase, center of gravity, hitch height, tyres pressure, and tyres design; in case of use of some electronic control  like diff-lock or draft control they will impact on the traction.
For Tyres, the traction depends on many design parameters like number of lugs, lug profile, lug thickness, carcass flexibility...Fixing a certain traction level some tyre can slip a few percent units less than other brands,  that involves the tyre is foundamental ring in the kinemathic chain efficiency even if it is not fully understood by the tractor Companies.

      tration  Traction2

Traction Slip figure displays a typical figure measured in field: data have been recorded @ 4 kHz: the blue dot cloud has been calculated and averaged by using the 20 Hz Algoritm, the red curve has been achieved by using  the Sieve Algoritm (traction by classes of slip) that is a very precise interpolation, the black curve is the polinomial made by Excell good up to 50% of slip but it is faulty further when the number of samples decrease.
Traction Efficiency figure displays the ratio Traction / Weight, were Weight i the real dynamic weight on tyre (a typical mistake of many engineers is to use the stationary weight without taking in account of the weight transfer due to the traction momentum), the figure gives us an idea of the difference of traction between tyre brands.

Traction_Slip figure
Traction Efficiency





Sorry, still    under construction
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